Electrically operated valve means

ABSTRACT

A plurality of separate pneumatically operated actuators disposed in aligned and abutting relation to provide a linear positioning unit having opposed ends with each actuator being individually operable to linearly extend itself when actuated and thereafter to linearly collapse itself when deactuated whereby one end of the unit will be correspondingly linearly extended relative to the other end thereof and thereafter be linearly collapsed relative to the other end thereof. A control device being operatively interconnected to the one end of the positioning unit to be controlled in relation to the position of the one end relative to the other end thereof and electrically operated ball valve means including opposed valve seats and shock-absorbing spring means for directing a source of pneumatic fluid to at least one of the actuators to extend the one end of the unit by the degree of actuation of the one actuator and for thereafter disconnecting the source from that one actuator to collapse the one end of the unit by the degree of deactuation of the one actuator.

United States Patent [72] Inventor Louis M. Puster Knoxville, Tenn.

[21] Appl. No. 865,041

[22] Filed Oct. 9, 1969 [45] Patented Oct. 12, 1971 [73] AssigneeRobertshaw Controls Company Richmond, Va.

[54] ELECTRICALLY OPERATED VALVE MEANS 18 Claims, 10 Drawing Figs.

FOREIGN PATENTS 842,238 7/1960 Great Britain ABSTRACT: A plurality ofseparate pneumatically operated actuators disposed in aligned andabutting relation to provide a linear positioning unit having opposedends with each actuator being individually operable to linearly extenditself when actuated and thereafter to linearly collapse itself whendeactuated whereby one end of the unit will be correspondingly linearlyextended relative to the other end thereof and thereafter be linearlycollapsed relative to the other end thereof. A control device beingoperatively interconnected to the one end of the positioning unit to becontrolled in relation to the position of the one end relative to theother end thereof and electrically operated ball valve means includingopposed valve seats and shock-absorbing spring means for directing asource of pneumatic fluid to at least one of the actuators to extend theone end of the unit by the degree of actuation of the one actuator andfor thereafter disconnecting the source from that one actuator tocollapse the one end of the unit by the degree of deactuation of the oneactuator.

PATENTEnncnzlsn $611,878

SHEET 2 0r 5 INVENTOR. LOUIS M. PUSTER HIS ATTORNEYS PATENTED 06H 2 ISYISHEET 3 OF 5 INVbNTOR. LOUIS M. PUSTER HIS ATTORNEYS PATENTEflucnzlsn F3611 878 sum u or 5 Lin INVENTOR.

83 K LOUIS M. PUSTER F |G.8 BY

HIS ATTORNEYS ELECTRICALLY OPERATED VALVE MEANS This invention relatesto an improved electrically operated valve means.

It is well known that various pneumatically operated positioning deviceshave been provided wherein a controlled device has its operatingcondition changed in proportion to the degree of actuation of one. ormore pneumatically operatedactuators formingpart of the positioningapparatus.

It is a feature of thisinvention to provide an improved electricallyoperated valve means A for such a pneumatically operated positioningapparatus or the like.

In particular, one embodiment of this invention provides a tubularhousing member having aplurality of separate pneu- .matically operatedactuators disposed in aligned and abutting relation in a tubular housingto provide. a linear positioning unit having opposed. ends, eachactuator being individually operable to readily extend itself whenactuated and thereafter to linearly collapse itself when deactuatedwhereby one end of the unit will be correspondingly linearly extendedrelative to the other end thereof and thereafter be linearly collapsedrelative to the other end thereof. A control device is operativelyinterconnected'to the one. end of the positioning unit to be controlledin relation to the position of the end of the unit relative to the otherend-thereof. A source of pneumatic fluid is directed to a controlmeans'which comprises individual solenoid-operated valvesfor each of thepneumatically operated actuators whereby when-one of thesolenoid-operated valves directs the pneumatic source to-its respectiveactuator to extend the one end ofthe unit by the degree of actuation ofthat one actuator, the control device is proportionally adjusted.

Therefore, it is an object of this invention to provide an improvedelectrically operated valve means.

Another object of this invention'is to provide an improved systemutilizing such valve means.

Other objects, uses and advantages of this invention are apparent from areading of this description which proceeds with reference to theaccompanying drawings forming a part thereof and wherein:

FIG. 1 is a side view, partially in crosssection, illustrating theimproved pneumatically operated positioning apparatus and control systemof this invention.

FIG. 2 is a cross-sectional view taken substantially on line 2-2 of FIG.1.

FIG. 3 is an enlarged, fragmentary, cross-sectional view of a portion ofthe positioning apparatus of FIG. 1 illustrating certain of thepneumatically operated actuators thereof in actuated condition.

FIG. 4 is a top perspective view of one of the improved pneumaticallyoperated actuators of the apparatus of FIG. 1.

FIG. 5 is an exploded perspective view of the parts forming thepneumatic actuator of FIG. 4.

FIG. 6 is a cross-sectional view of the pneumatically operated actuatorof FIG. 4 and is taken substantially on line 66 of FIG. 4.

FIG. 7 is a top view of one of the solenoid-operated valve means for theapparatus of FIG. 1.

FIG. 8 is a partial cross-sectional view of the solenoidoperated valveof FIG. 7 and is taken on line 8-8 thereof.

FIG. 9 is a left-hand end view of the solenoid-operated valve of FIG. 8.

FIG. 10 is a right-hand end view of the solenoidoperated valve of FIG.8.

While the various features of this invention are hereinafter describedand illustrated as being particularly adapted to provide electricallyoperated valve means for apositioning apparatus, it is to be understoodthat the various features of this invention can be utilized singly or inany combination thereof to provide valve means for other devices asdesired.

Therefore, this invention is not to be limited to only the embodimentillustrated in the drawings, because the drawings are merely utilized toillustrate-one of the wide variety of uses of this invention.

Referring now to FIGS. 1 and 2, the improved pneumatically operatedpositioning apparatus and control system of this invention is generallyindicated by the reference-numeral l0 and comprises a frame means 11carrying a device 12 that is adapted to have its output varied inrelation to the position of an actuator rod 13 relative to the frame 11,the actuator rod 13 being suitably coupled to an indicating pointer 14which'indicates to the viewer the position of the actuator rod 13 and,thus, the set output function of the control device 12.

A cylindrical housing means 15 is secured to the frame means 11 in anysuitable manner, such as by brackets 16 respectively at the opposed ends17 and 18 of the cylinder 15. The opposed ends 17 and 18 of the cylinder15 are respectively closed by end closure caps 19 and 20 held thereon inplug fashion by threaded retainers 21 respectively threaded to theexternally threaded ends 17 and 18 of the cylinder 15, the end closuresl9 and 20 respectively having externally threaded extensions projectingthrough suitable openings in the brackets 16 to receive nuts 22 tothereby fasten thesleeve or cylinder 15 to the frame means 11.

A plurality of separate pneumatically operated actuators 23 arerespectively disposed in stacked; aligned relationin the cylinder 15with the bottom actuator '23 resting against the lower end cap 20whereby such actuators 23 are disposed in aligned abuttingrelation toprovide a linear positioning unit, generally indicated by the referencenumeral 24,- inthe cylinder 15 with the positioning unit having opposedends 25 and 26.

A dashpot means, generally indicated'by the reference numeral 27 in FIG.1, is also disposed in the cylinder'or housing means 15 and comprises apiston 28 and cooperating cylinder 29 with the cylinder 29 being movablein the housing 15 and having its lower end 30 abutting against the upperend 25of the positioning unit 24. The piston 28is held stationaryrelative to the cylinder 29and has a stem 3l'projecting out of the upperend 32 of the cylinder'29 and is threadedly interconnected to the upperend cap 19 of the housing means 15 whereby the position of the piston 28can be adjusted relative to the housing means 15, if desired.

The cylinder 29 of the dashpot means 27 is filled with a suitabledampening fluid, such as silicone, so as to provide means for cushioninglinear movement of the positioning unit 24 in the housing means 15 tothe actuator rod 13 of the control device 12 as will be apparenthereinafter, the dashpot means 27 operatively interconnecting thepositioning unit 24 to the actuating rod 13 of the control device 12 bysuitable linkage means 33.

In particular, the upper end 32 of the cylinder 29' of the dashpot means27 has an arm 34 fastened therethrough and projecting out through a slot35 in the housing means 15 so as to be disposed in engagement with a pin36 transversely carried by a pivotally mounted lever 37 which isinterconnected through linkage means 38, 39 and 40 to the actuator rod13 and set point indicator 14 so that upward and downward movement ofthe arm 34 of the dashpot means 27 will cause correspondingly downwardand upward movement of the actuating rod 13 as will be apparenthereinafter. In order to maintain the pin 36 of the lever 37 inengagement against the arm 34 of the dashpot means 27, a suitabletension spring 41 is provided and has one end 42 interconnected to thelink 38 and the other end 43 thereof interconnected to the upper bracket16.

Since the actuators 23 of the positioning unit 24 are separate from eachother, as well as from the dashpot means 27 in the housing means 15,another tension spring is pro vided and has one end 45 interconnected tothe-arm 34 and the other end 46 thereof interconnected to the lowerbracket 16 whereby the force of thetension spring44 normally tends tomaintain all of the actuators 23 in their collapsed and deactuatedcondition and with the cylinder 29 of the dashpot means 27in engagementwith the upper end 25 of the positioning unit 24.

Each actuator 23 of the positioning unit 24 is adapted to beindividually operable to linearly extend itself when actuated andthereafter to linearly collapse itself when deactuated whereby the upperend 25 of the positioning unit 24 will be correspondingly linearlyextended in an upward direction and thereafter be linearly collapsed ina downward direction depending upon the degree of actuation of theparticular actuator 23 and the degree of deactuation thereof. Since suchupward and downward movement of the upper end 25 of the positioning unit24 operates to correspondingly move the cylinder 29 of the dashpot means27, the dampening fluid in the cylinder 29 serves to dampen suchmovement of the upper end 25 of the positioning unit 24 to the actuatingrod 13 of the control device 12 so that the control device 12 is slowlychanged and thereby does not have sudden overshoots or undershoots, thepin 36 sliding on the arm 34 of the cylinder 29 of the dashpot means 27so as to permit clockwise or counterclockwise movement of the lever 37depending upon upward of downward movement of the end 25 of thepositioning unit 24.

A plurality of electrically operated valve means 47 are respectivelysecured to the frame means 11 with one valve means 47 being provided foreach pneumatically operated actuator 23 which, in the embodimentillustrated in FIG. 1, comprises nine valve means 47 and ninepneumatically operated actuators 23. Each valve means 47 is operativelyinterconnected to a pneumatic source 48 in a manner hereinafterdescribed and is adapted, when actuated, to direct the pneumatic source48 to its respective actuator 23 by an outlet conduit means 49 so as tolinearly extend or actuate that actuator 23. Thereafter, that particularvalve means 47 can disconnect the pneumatic source 48 from itsrespective actuator 23 while interconnecting the atmosphere thereto soas to deactuate its particular actuator 23 whereby the same willlinearly collapse under the force of the tension spring 44.

Each valve means 47, when deenergized, prevents communication betweenthe pneumatic source 48 and its respective actuator 23 whileinterconnecting its respective actuator 23 to the atmosphere. However,when the respective valve means 47 is energized, the same disconnectsthe atmosphere from its respective actuator 23 and interconnects thepneumatic source 48 thereto.

Each valve means 47 has a pair of terminals 50 and 51 with the terminals50 of the valve means 47 being respectively interconnected to anelectrical lead 52 that is interconnected to a power source line L Theother terminal 51 of each valve means 47 is interconnected to respectiveleads 53 which are adapted to be selectively, collectively or in anycombination thereof interconnected to the other power source lead L by asuitable control means 54, such as a computer, tape or card reader,etc., so as to control the operation of the control device 12 in amanner hereinafter set forth.

Each pneumatically operated actuator 23 can be formed in a like mannerand the details of one such pneumatically operated actuator 23 will nowbe described and reference is made to FIGS. 4, and 6.

As illustrated in FIGS. 4, 5 and 6, the actuator 23 comprises twocup-shaped housing members 55 and 56 formed in cylindrical form andrespectively having open ends 57 and 58, the open end 58 of thecup-shaped housing member 56 being inwardly offset and being externallythreaded at 59 so as to be threaded to the internal threaded portion 60of the other cupshaped housing member 55 whereby the thus-interconnectedcup-shaped housing members 55 and 56 define a cylinder means 61 having atransverse cross-sectional configuration closely resembling thetransverse cross-sectional configuration of the inside of the cylinderor housing means so as to be disposed in closed relation to the internalperipheral surface of the housing means 15 while permitting movementtherebctween for the aforementioned linear expansion and contraction ofthe positioning unit 24. A piston member 62 has an enlarged cylindricalportion 63 disposed in the open end 58 of the cup-shaped member 56 andhas an annular groove 64 receiving an annular O-ring 65 for sealingagainst the internal peripheral surface 66 of the housing member 56while pennitting axial movement of the piston member 62 relativethereto. The piston member 62 has its lower surface 166 interrupted by acavity 67 to cooperate with the housing member 56 to define a chamber 68therebetween.

In addition, the lower surface 166 of the piston member 62 is beveled at69 at the corner thereof so as to be in fluid communication with atransverse passage means 70 formed radially through the cup-shapedhousing member 56 and being interconnected to a tubular insert 71 thatis adapted to be interconnected to the respective conduit means 49 of arespective valve means 47 for permitting the pneumatic source 48 to bedirected to the cavity 68 of the actuator 23 or for interconnecting theatmosphere thereto.

The piston member 62 includes a reduced portion 72 cooperating with thelarge portion 63 to define an annular shoulder 73 for abutting againstthe inside surface 74 of the closed end 75 of the upper cup-shapedhousing member 55 so as to limit upward movement of the piston member 62when the actuator 23 is interconnected to the pneumatic source, thereduced portion 72 of the piston member 62 projecting out through asuitable opening 76 in the closed end 75 of the cupshaped housing member55 so as to have its flat end 77 for engaging against the cylinder means61 of the actuator 23 above the same in the positioning unit 24.

By providing the threaded relation 59 and 60 between the cup-shapedhousing members 55 and 56, the stroke or linear distance that the pistonmember 62 can travel in an upward direction in FIG. 6 when having itscavity 68 interconnected to the pneumatic source 48 can be readilyadjusted and once adjusted to the desired position, suitable setscrews78 can be tightened to hold the cup-shaped housing members 55 and 56 inthe desired adjusted threaded relation therebetween.

Therefore, it can be seen that each actuator 23 can have a differentstroke setting than the other actuator 23 as determined by theparticular threaded relation between the two cup-shaped housing members55 and 56 thereof which define the cylinder means 61 thereof, Therefore,with pressure applied to the tubing 71 of a particular actuator 23, thepiston member 62 moves up until the shoulder 73 thereof strikes againstthe end 75 of the housing member 55 and when the cavity 68 thereof isinterconnected to the atmosphere and a load is applied to the pistonmember 62 thereof, such as by the tension spring 44 of FIG. 1, thepiston 62 is driven downwardly until the same bottoms against the closedend 79 of the lower cup-shaped housing member 56.

Thus, it can be seen that each pneumatically operated ac tuator 23 ofthis invention can be formed of relatively simple and inexpensive partsto be assembled together in a simple and effective manner to permitseparate adjustment of the stroke thereof and can be disposed in thehousing means 15 to provide the positioning unit 24, the housing means15 having another slot 80 in the side thereof and out through which thetubing 71 of the actuators 23 can project to not only permit axialmovement of the actuators 23 in the housing means 15, but also to guidethe same in the housing means 15 and prevent rotational movementtherein.

The valve means 47 for the apparatus 10 of this invention are identicaland one such valve means 47 is illustrated in FIGS. 7-10 and will now bedescribed.

As illustrated in FIGS. 7-10, each valve means 47 comprises a twopiecebracket 81 with the lower part 82 thereof carrying a housing means 83supporting a solenoid coil 84 having its opposed ends respectivelyinterconnected to the terminals 50 and 51, the coil 84 having core means85 for attracting an armature or clapper 86 pivotally mounted to thebracket means 81 in any suitable manner at a point 87 intermediate itsopposed ends 88 and 89. The armature or clapper 86 is normally urged tothe position illustrated in FIG. 8 by a tension spring 90 having one end91 interconnected to the end 89 of the ar mature 86 and the other end 92interconnected to the bracket means 81. An opening 93 passes through thearmature 86 and is covered at its lower end by a leaf spring 94 attachedto the armature 86 by a pair of eyelets 95 passing through suitableopenings in the leaf spring 94 which are oversized so that the leafspring 94 can bow relative to the armature 86 as will be apparenthereinafter.

Another housing member 96 is carried by an upper arm 97 of the bracketmeans 81 and has a cavity 98 fonned therein and receiving a valve seatmember 99 that cooperates with an O-ring 100 to seal the cavity 98 abovean outwardly directed annular flange 101 of the valve seat member 99from the exterior of the housing 96. A stepped bore 102 passes throughthe valve seat member 99 whereby the lower end 103 of the bore 102 isexposed to the atmosphere and the upper end 104 of the bore 102 is inaligned relation with a passage 105 formed in the housing 96 andinterconnected to a cross passage 106 formed in the housing 96 and beingrespectively interconnected at opposed ends to tubular nipple fitting107 and 108 as illustrated in FIG. 7.

The upper end 104 of the stepped bore 102 of the valve sear member 99 isalsoin communication with a transverse recess 109 that communicates withthe cavity 98.

The juncture 110 that the passage 105 makes with the cavity 98 in thehousing member 96 defines a valve seat adapted to be opened andclosed bya ball valve member 111. Similarly, the stepped bore 102 in the valveseat member 99 defines a valve seat 112 adapted to be opened and closedby the ball valve 111.

An actuating rod 113 projects loosely into the end 103 of the steppedbore 102 so as to have its upper end 114 engageable with the ball valvemember 111 and its lower end 115 engageable against the leaf spring 94of the clapper or armature 86 Thus, when the coil 84 of the particularvalve means 47 is deenergized, the tension spring 90 maintains thearmature 86 in the position illustrated in H6. 8 wherebythe armature 86,through the pushrod 113, maintains the ball valve member 111 away fromthe valve seat 112 and into sealing engagement with the valve seat 110so that the cavity 98 is directly interconnected to the atmospherethrough the cross recess 109 and open valve seat 112. However, when thecoil 84 of the particular valve means 47 is energized by beinginterconnected to the power source leads L and L by the control device54, the end 88 of the armature 86 is pulled downwardly in FIG. 8 so thatthe push rod 113 follows such movement and permits the ball valve member111 to move away from the valve seat 110 and into sealing engagementwith the valve seat 112 whereby the cavity 98 is sealed from theatmosphere and is in fluid communication with the cross passage 106 inthe housing means 96.

The cavity 98 of the housing means 96 is always in communication with apassage means 116 which receives a tubular extension nipple 117 that isadapted to be interconnected to the conduit means 49 that leads to therespective actuator 23 for that valve means 47.

As illustrated in FIG. 1, all of the cross passages 106 of the ninevalve means 47 are adapted to be interconnected to the pneumatic source48 by having the nipple extension 107 on the lower valve means 47 ofFIG. 1 fluidly interconnected to the pneumatic source 48 by a couplingconduit means 118 and its other nipple extension 108 interconnected tothe nipple means 107 of the next adjacent valve means 47 by a couplingconduit means 119. Thus, all of the valve means 47 have the nippleextensions 107 and 108 thereof coupled in series with the uppermostvalve means 47 in FIG. 1 having its nipple extension 108 sealed from theatmosphere.

Therefore, in the control system of this invention, when a particularsolenoid coil 84 of a particular valve means 47 is energized, the end 88of the armature clapper 86 thereof is pulled downwardly against the coremeans 85 and the stem or rod 113 follows such movement and is ofsufficient length to permit the ball valve member 111 to seat againstthe vent valve seat 112 so as to permit pressurized fluid which issupplied through the tubing adapters 107 or 108 to flow seat the passage106 and opened valve seat 110 to the outlet passage 116 and, thus, toits respective actuator means 23. When that particular solenoid coil 84is subsequently deenergized, the tension spring snaps the left-hand end88 of the clapper 86 upwardly so that the stem or rod 113 engages theball valve member 111 and unseats it from the vent valve seat 112 andforces it against the supply valve seat 110 to close off the supply ofair pressure from passage and venting the pressurized air from itsinterconnected actuator 23 through the open vent valve seat 112 to theatmosphere, such upward snapping movement of the armature 86pennittingthe leaf spring 94 to bow and absorb the shock of the valve member 86striking the stem or rod 86 and its seating action of the ball 111against the supply valve seat 110.

The operation of the apparatus and control system 10 of this inventionwill now be described.

With all of the actuators 23 in their deactuated condition, thepositioning unit 24 is in the position illustrated in FIG. 1 whereby theactuating rod 13 of the control device 12 is at one setting thereof.However, should it be desired. or determined that the output of thecontrol device 12 should be increased or decreased as the case may be,the control means 54 interconnects the power source leads L to theparticular lead 53 of the particular valve means 47 or to several leads53 of particular valve means 47 as the case may be so that one or moreof the valve means 47 will have the coils 84 thereof energized.

Pressurized fluid is then adapted to flow from the source 48 to therespective actuators 23 of the energized valve or valves 47interconnected therewith. Thus, the pistons 62 of the actuators 23extend in the manner illustrated'in P16. 3 moving the end 25 of thestack 24 upwardly the amount of the actuated piston strokes. The dashpotcylinder 29 and arm 34 also move up, rotating the lever 37 through thepin 36 in a clockwise movement of the lever 37 through the linkage 38,39 and 40 move the indicator 14 in a clockwise direction and theactuating rod 13 in an upward direction so as to change the setting ofthe control device 12 proportionally to the amount of up movement of theend 25 of the positioning unit 24, the dashpot means 27 serving as adampening device so that the set point of the control device 12 isslowly changed eliminating sudden overshoots and jumping of the controldevice 12.

If the solenoid valves 47 previously energized are now deenergized,pressurized air is vented from the actuated actuators 23 through theirrespective deenergized solenoid valves 47 permitting the tension spring44 to return the extended pistons 62 to their originally collapsedconditions so that the cylinder 29 of the dashpot means 27 movesdownwardly permitting the lever 37 to rotate in a counterclockwisedirection under'the force of the tension spring 41 and move the setpoint indicator 14 back to its original position and moving the actuatorrod 13 back to its original position so that the control device 12 isset back to its original value.

The rate of action of the positioning unit 24 for changing the settingof the control device 12 is determined by the dashpot means 27. Thisrate of movement in the dashpot means 27 is determined by the viscosityof the fluid in the cylinder 29 and the clearance between the outsidediameter of the piston 28 and the inside diameter of the cylinder 29since the piston 28 is held stationary and the cylinder 29 is moved byspring 44 forcing fluid in the cylinder means 29 past the stationarypiston 28.

From the above description, it can be seen that the amount of set pointchange of the control device 12 is directly proportional to the amountof stroke that the actuators 23 will make when actuated. Therefore, withthe nine actuators 23 illustrated, nine different amounts of set pointchange can be fed into the control device 12. By energizing the solenoidvalves in combination and choosing proper strokes for the differentactuators 23, almost any set point change to the control device 12 canbe achieved. The solenoid valves 47 can be energized by many differentdevices, such as a computer, tape or card reader, etc.

For example, to fit a computer to the apparatus of this invention, thefollowing description will be based on Binary numbering logic althoughit is to be understood that other Logic systems could be used such asdecimal, Binary decimal, etc.

However, with a binary numbering logic system, the strokes of the nineactuators 23 will be functions of the following binary numbering system:l, 2, 4, 8, 16, 32, 64, 128 and 256 which totals to 51 1. Assuming eachnumber represents l F., the system 10 can obtain a 0 F. to 511 F. rangechange in 1 F. steps by choosing the right combination of actuators 23.For example, 200 F. is achieved by actuating the 128 F., 64 F. and the 8F. actuators 23 while 199 F. is achieved by actuating the 128 F., 64 F.,4 F. 2 F. and 1 F. actuators 23. Actually, each actuator 23 will make astroke which is some multiple of the above number to obtain more totaltravel. in this instance, the actuators 23 can be chosen for stroketravel of 0.0025 of an inch per 1 F. Therefore, the l F. actuator 23makes 0.0025-inch travel; the 2 F. actuator 23 makes 0.005- inch travel;the 4 F. actuator 23 makes 0.0l0-inch travel; the 8 F. actuator 23 makes0.020-inch travel; the 16 F. actuator 23 makes 0.040-inch travel; the 32F. actuator 23 makes 0.080-inch travel; the 64 F. actuator 23 makes0.160-inch travel; the 128 F. actuator 23 makes 0.320-inch travel; andthe 256 F. actuator 23 makes 0.640-inch travel.

Therefore, for a total of 511 F. span controller, the stack 24 ofactuators 23 would have a total travel of 1.2775 inches in 0.0025-inchsteps.

Having available a total of 511 F. span controller, each span less thanthat could be used; for instance, 200 F. say from 50 F. to 250 F. with32 F., 16 F., and 2 F. actuators 23 actuated, the set point indicator 14would be calibrated to read 50 F. To prevent damaging overtravel, stem31 can be adjusted to bottom out on the inside of the housing orcylinder 29 and serve as a stop for the apparatus 10.

Therefore, it can be seen that not only does this invention provide animproved electrically operated valve means, but also this inventionprovides an improved system utilizing such valve means or the like.

What is claimed is:

1. Valve construction means comprising a housing means having a pair ofopposed valve seats, a valve member carried by said housing means andbeing movable between said valve seats for opening either one of saidvalve seats while closing the other valve seat, a plunger movablycarried by said housing means and projecting through one of said valveseats to abut said valve member, electrical coil means interconnected tosaid housing means, and a movable annature means moving to one positionwhen said coil means is deenergized and moving to another position whensaid coil means is energized, said armature means being operativelyinterconnected to said housing means and carrying spring means that iscontinuously engageable with said plunger to move said plunger insubstantial unison therewith and thereby move said valve member betweenits operating positions, said plunger being out of engagement with saidvalve member when said armature means is in said other position thereofso that said valve member can close one of said valve seats and being inengagement with said valve member when said armature means is in saidposition thereof so that said valve member can close the other of thevalve seats whereby said spring means absorbs shocks between saidplunger and said armature means when said armature means is moving fromsaid other position thereof to said one position thereof.

2. Valve construction means as set forth in claim 1 wherein said housingmeans has a passage means leading from the exterior of said housingmeans to the space between said valve seats so as to be fluidlyinterconnected to the particular opened valve seat.

3. Valve construction means as set forth in claim 1 wherein said housingmeans has a passage means leading from the exterior of said housingmeans to one of said valve seats, said plunger being loosely disposed insaid passage means.

4. Valve construction means as set forth in claim 3 wherein said passagemeans interconnects the atmosphere with said one valve seat.

5. Valve construction means as set forth in claim 1 wherein said housingmeans has a passage means leading from the exterior of said housingmeans to one of said valve seats, said passage means being substantiallyT-shaped with the cross thereof interconnecting opposed exterior partsof said housing means to said one valve seat at the end of the leg ofsaid T- shaped passage means.

6. Valve construction means as set forth in claim 5 wherein another likehousing means and its associated parts are interconnected to thefirst-named housing means by a conduit means fluidly interconnecting oneend of the cross of the T- shaped passage means of the first-namedhousing means to one end of the cross of the T-shaped passage means ofsaid other housing means.

7. Valve construction means as set forth in claim I wherein said springmeans comprises a leaf spring, said armature means having an openingtherethrough receiving one end of said plunger, said leaf springspanning said opening and being engaged by said one end of said plunger.

8. Valve construction means as set forth in claim 1 wherein a framemeans interconnects said housing means to said coil means, said armaturebeing pivotally mounted to said frame means.

9. Valve construction means as set forth in claim 8 wherein spring meansis carried by said frame means and is interconnected to said armature totend to maintain said armature in said one position thereof.

10. In combination, a pneumatic source, a pneumatically operatedactuator, a housing means having a pair of opposed valve seats, firstmeans fluidly interconnecting said source to one of said valve seats, avalve member carried by said housing means and being movable betweensaid valve seats for opening either one of said valve seats whileclosing the other valve seat, a plunger movably carried by said housingmeans and projecting through one of said valve seats to abut said valvemember, electrical coil means interconnected to said housing means, amovable armature means moving to one position when said coil means isdeenergized and moving to another position when said coil means isenergized, said armature means being operatively interconnected to saidhousing means and carrying spring means that is continuously engageablewith said plunger to move said plunger in substantial unison therewithand thereby move said valve member between its operating positions, saidplunger being out of engagement with said valve member when saidarmature means is in said other position thereof so that said valvemember can close one of said valve seats and being in engagement withsaid valve member when said armature means is in said one positionthereof so that said valve member can close the other of the valve seatswhereby said spring means absorbs shocks between said plunger and saidarmature means when said armature means is moving from said otherposition thereof to said one position thereof, said housing means havinga passage means leading from the exterior of said housing means to thespace between said valve seats so as to be fluidly interconnected to theparticular opened valve seat, and second means fluidly interconnectingsaid actuator to said passage means.

11. A combination as set forth in claim 10 wherein said housing meanshas another passage means leading from the exterior of said housingmeans to the other of said valve seats, said plunger being looselydisposed in said passage means.

12. A combination as set forth in claim ll wherein said other passagemeans interconnects the atmosphere with said other valve seat.

13. A combination as set forth in claim 10 wherein said first meansincludes a passage means in said housing means leading from the exteriorof said housing means to said one valve seat, said passage means beingsubstantially T-shaped with the cross thereof interconnecting opposedexterior parts of said housing means to said one valve seat at the endof the leg of said T- shaped passage means.

14 A combination as set forth in claim 13 wherein another like housingmeans and its associated parts is interconnected to the first-namedhousing means by a conduit means fluidly interconnecting one end of thecross of the T-shaped passage means of a first-named housing means toone end of the cross of the T-shaped passage means of said other housingmeans whereby said source is interconnected to said one valve seat ofeach housing means.

15. A combination as set forth in claim wherein said spring meanscomprises a leaf spring, said armature means having an openingtherethrough receiving one end of said plunger, said leaf springspanning said opening and being engaged by said one end of said plunger.

16. A combination as set forth in claim 10 wherein a frame meansinterconnects said housing means to said coil means, said armature beingpivotally mounted to said frame means.

17. A combination as set forth in claim 16 wherein spring means iscarried by said frame means and is interconnected to said armature totend to maintain said armature in said one position thereof.

18. A combination as set forth in claim 10 wherein another like housingmeans and its associated parts are provided, said first means alsofluidly interconnecting said source to the one valve seat of said otherhousing means.

1. Valve construction means comprising a housing means having a pair ofopposed valve seats, a valve member carried by said housing means andbeing movable between said valve seats for opening either one of saidvalve seats while closing the other valve seat, a plunger movablycarried by said housing means and projecting through one of said valveseats to abut said valve member, electrical coil means interconnected tosaid housing means, and a movable armature means moving to one positionwhen said coil means is deenergized and moving to another position whensaid coil means is energized, said armature means being operativelyinterconnected to said housing means and carrying spring means that iscontinuously engageable with said plunger to move said plunger insubstantial unison therewith and thereby move said valve member betweenits operating positions, said plunger being out of engagement with saidvalve member when said armature means is in said other position thereofso that said valve member can close one of said valve seats and being inengagement with said valve member when said armature means is in saidposition thereof so that said valve member can close the other of thevalve seats whereby said spring means absorbs shocks between saidplunger and said armature means when said armature means is moving fromsaid other position thereof to said one position thereof.
 2. Valveconstruction means as set forth in claim 1 wherein said housing meanshas a passage means leading from the exterior of said housing means tothe space between said valve seats so as to be fluidly interconnected tothe particular opened valve seat.
 3. Valve construction means as setforth in claim 1 wherein said housing means has a passage means leadingfrom the exterior of said housing means to one of said valve seats, saidplunger being loosely disposed in said passage means.
 4. Valveconstruction means as set forth in claim 3 wherein said passage meansinterconnects the atmosphere with said one valve seat.
 5. Valveconstruction means as set forth in claim 1 wherein said housing meanshas a passage means leading from the exterior of said housing means toone of said valve seats, said passage means being substantially T-shapedwith the cross thereof interconnecting opposed exterior parts of saidhousing means to said one valve seat at the end of the leg of saidT-shaped passage means.
 6. Valve construction means as set forth inclaim 5 wherein another like housing means and its associated parts areinterconnected to the first-named housing means by a conduit meansfluidly interconnecting one end of the cross of tHe T-shaped passagemeans of the first-named housing means to one end of the cross of theT-shaped passage means of said other housing means.
 7. Valveconstruction means as set forth in claim 1 wherein said spring meanscomprises a leaf spring, said armature means having an openingtherethrough receiving one end of said plunger, said leaf springspanning said opening and being engaged by said one end of said plunger.8. Valve construction means as set forth in claim 1 wherein a framemeans interconnects said housing means to said coil means, said armaturebeing pivotally mounted to said frame means.
 9. Valve construction meansas set forth in claim 8 wherein spring means is carried by said framemeans and is interconnected to said armature to tend to maintain saidarmature in said one position thereof.
 10. In combination, a pneumaticsource, a pneumatically operated actuator, a housing means having a pairof opposed valve seats, first means fluidly interconnecting said sourceto one of said valve seats, a valve member carried by said housing meansand being movable between said valve seats for opening either one ofsaid valve seats while closing the other valve seat, a plunger movablycarried by said housing means and projecting through one of said valveseats to abut said valve member, electrical coil means interconnected tosaid housing means, a movable armature means moving to one position whensaid coil means is deenergized and moving to another position when saidcoil means is energized, said armature means being operativelyinterconnected to said housing means and carrying spring means that iscontinuously engageable with said plunger to move said plunger insubstantial unison therewith and thereby move said valve member betweenits operating positions, said plunger being out of engagement with saidvalve member when said armature means is in said other position thereofso that said valve member can close one of said valve seats and being inengagement with said valve member when said armature means is in saidone position thereof so that said valve member can close the other ofthe valve seats whereby said spring means absorbs shocks between saidplunger and said armature means when said armature means is moving fromsaid other position thereof to said one position thereof, said housingmeans having a passage means leading from the exterior of said housingmeans to the space between said valve seats so as to be fluidlyinterconnected to the particular opened valve seat, and second meansfluidly interconnecting said actuator to said passage means.
 11. Acombination as set forth in claim 10 wherein said housing means hasanother passage means leading from the exterior of said housing means tothe other of said valve seats, said plunger being loosely disposed insaid passage means.
 12. A combination as set forth in claim 11 whereinsaid other passage means interconnects the atmosphere with said othervalve seat.
 13. A combination as set forth in claim 10 wherein saidfirst means includes a passage means in said housing means leading fromthe exterior of said housing means to said one valve seat, said passagemeans being substantially T-shaped with the cross thereofinterconnecting opposed exterior parts of said housing means to said onevalve seat at the end of the leg of said T-shaped passage means.
 14. Acombination as set forth in claim 13 wherein another like housing meansand its associated parts is interconnected to the first-named housingmeans by a conduit means fluidly interconnecting one end of the cross ofthe T-shaped passage means of a first-named housing means to one end ofthe cross of the T-shaped passage means of said other housing meanswhereby said source is interconnected to said one valve seat of eachhousing means.
 15. A combination as set forth in claim 10 wherein saidspring means comprises a leaf spring, said armature means having anopening therethrough receiving one end of said plunger, said leaf springspanning Said opening and being engaged by said one end of said plunger.16. A combination as set forth in claim 10 wherein a frame meansinterconnects said housing means to said coil means, said armature beingpivotally mounted to said frame means.
 17. A combination as set forth inclaim 16 wherein spring means is carried by said frame means and isinterconnected to said armature to tend to maintain said armature insaid one position thereof.
 18. A combination as set forth in claim 10wherein another like housing means and its associated parts areprovided, said first means also fluidly interconnecting said source tothe one valve seat of said other housing means.